Delamination toughening in a low carbon microalloyed steel plate rolled in the dual-phase region

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:766

Article

Shen, X. J.¹  Li, D. Z.¹  Tang, S.¹  Chen, J.¹  Fang, H.^2,3  Wang, G. D.¹ 

[1] Northeastern Univ, State Key Lab Rolling & Automat, POB 105,11,Lane 3,Wenhua Rd, Shenyang 110819, Liaoning, Peoples R China

[2] Delft Univ Technol, Fac Sci Appl, Fundamental Aspects Mat & Energy Grp, Mekelweg 15, NL-2629 JB Delft, Netherlands

[3] Delft Univ Technol, Novel Aerosp Mat Grp, Fac Aerosp Engn, Kluyverweg 1, NL-2629 HS Delft, Netherlands

关键词: Steel plates;    Delamination toughening;    Elongated and ultrafine-grained microstructure;    Crystallographic texture;   

DOI  :  10.1016/j.msea.2019.138342

来源: Elsevier

【 摘 要 】

It is still a big challenge to obtain excellent low-temperature toughness for bulk steel materials. Delamination is an effective method to improve low-temperature toughness. In the present study, delamination toughening in a low carbon microalloyed steel plate with elongated and ultrafine-grained microstructure rolled in the dual-phase region has been investigated in detail. When toughness was measured along normal direction, the steel plate had a high upper shelf energy and no delamination occurred in the upper shelf region. A large delaminated crack parallel to rolling plane started to appear and changed the propagation path of main crack when testing temperature was lower than -60 degrees C. We find this kind of delamination induces a second upper shelf in the Charpy transition-temperature curve. The second upper shelf, reaching up to 300 J in the temperature range of -60 degrees C to -140 degrees C, results in excellent low-temperature toughness for the steel plate, and the ductile-brittle transition temperature is lowered to -157 degrees C. The developed steel plate also has high low-temperature toughness measured along transverse direction due to delamination. The effect factors on upper shelf energy, delamination mechanism and delamination toughening are discussed.

【 授权许可】

Free